Electrophotographic copying machine

ABSTRACT

An electrophotographic copier comprises a photosensitive drum including a photoconductive layer and an outer insulative layer. Apparatus for forming and developing an image of an original on the drum surface is selectively supported peripherally thereof as is apparatus for feeding copy material to the drum surface, for transferring developed images to the copy paper and for cleaning the drum surface. The developing, image transfer, fixing, cleaning, and copy separating devices are supported on a single unitary support member which is manually movable into and out of the operative position adjacent to the drum surface. A carrier for supporting the original is arranged for reciprocating movement with respect to the drum. Preferred embodiments of such peripherally supported apparatus are also disclosed.

United States Patent Ito et al.

[ Sept. 5, 1972 [54] ELECTROPHOTOGRAPHIC COPYING MACHINE [72] Inventors:Yoshio Ito, Tokyo; Haiime Katayama, Kawasaki; Masaru Yamaguchi, Tokyo,all of Japan [73] Assignee: Canon Kabushiki Kaisha, Tokyo,

Japan [22] Filed: April 30, 1970 [21] Appl. No.: 33,219

[30] Foreign Application Priority Data May 2, 1969 Japan ..44/34714 Aug.12, 1969 Japan ..44/63653 [52] US. Cl. ..355/8, 355/3, 355/11 [51] Int.Cl. ..G03g 15/00 [58] Field of Search ..355/3, 8, 13, 14,50, 65, 66

[56] References Cited UNITED STATES PATENTS 3,506,259 4/1970 Caldwell eta1. ..355/3 X 2,959,095 11/1960 Magnusson ..355/11 X 3,399,610 9/1968Eilhom ..355/14 X 3,418,047 12/1968 Lee et al. ..355/13 X 2,740,8954/1956 Miller ..355/91 X 3,069,990 12/ 1962 Eisbeing et al ..355/ 103 X3,309,960 3/1967 Delplanque ..355/3 3,521,950 7/1970 Gardner et a1..355/3 Primary Examiner-J0hn M, Horan Assistant Examinew-Kenneth C.Hutchison Attorney-Watson, Leavenworth & Kelton ABSTRACT member which ismanually movable into and out of the operative position adjacent to thedrum surface. A carrier for supporting the original is arranged forreciprocating movement with respect to the drum. Preferred embodimentsof such peripherally supported apparatus are also disclosed.

11 Claims, 18 Drawing Figures PATENTEDSEP 5:912

SHEET 3 [1F 9 PATENIEDSEP 5 m2 sum 5 of 9 PATENTEDsEP Sum 3.689.146

saw 8 0f 9 FIG. l2(2) ELECTROPHOTOGRAPHIC COPYING MACHINE The presentinvention relates to an improved electrophotographic copying machine andmore particularly to an electrophotographic copying machine in which aphotosensitive member having a photoconductive layer interposed betweena surface insulating layer and a conductive or insulating member isemployed so that in image of a sheet-like original or an original havinga relatively greater thickness may be automatically,

quickly and economically formed upon an image recording medium such asordinary paper.

Electrophotographic copying machines for reproducing copies of asheet-like original as well as an original having a relatively greaterthickness are divided into two types, one type employing photosensitivepapers and the other type employing no photosensitive paper, that is,the so-called Xerographic type. In the former type photosensitive papersare used so that cost is considerably more than with ordinary paper. Inthe latter type, inexpensive ordinary paper is used as an imagerecording medium, but since a photosensitive drum having aphotosensitive layer formed by vacuum deposition of selenium is used,the surface of the photosensitive layer tends to be directlymechanically damaged in repetitive use of the drum. Thus, there is aproblem regarding durability of the drum with resultant increased cost.Mechanically, the original is held in stationary position while theoptical system as well as the photosensitive drum inside the machine aredriven in synchronism with each other so that the copying machine musthave a highly precise mechanism which is inevitably large in size.

Therefore, one of the objects of the present invention is to provide animproved electrophotographic copying machine compact in size, capable ofhigh speed copying operation, especially capable of reducing the copyingor reproduction time required for reproducing a single copy, simple inoperation, and inexpensive to manufacture. This object may be attainedby employing the above described photosensitive body coated with aninsulating layer of a polyester resin having considerable mechanicaldurability, for example Mylar (Trade Name) and by using as an imagerecording medium an ordinary paper or the like, so as to reproducecopies from a sheet-like original or an original having a relativelygreater thickness which is moved during exposure.

Another object of the present invention is to provide an improvedelectrophotographic copying machine having a mechanism for separating,from a photosensitive drum, copy paper which is electrostaticallyattracted thereto.

A feature of the present invention is to provide an improvedelectrophotographic copying machine having fixing means for fusing andfixing to a copy paper a powder image consisting of thermoplasticresinous toner, said fixing means having a conveyor belt forelectrostatically attracting the copy paper thereto and preheating theconveyor belt by air heated by heating elements, which directly heat theconveyor belt, at a position at which the copy paper is loaded upon theconveyor belt, thereby preventing the copy paper from being curled.

According to one aspect of the present invention, an original carrier isdisposed at the top of the housing of the electrophotographic copyingmachine. The original carrier is provided with a pressure plate forholding in stationary position a sheet-like original or an originalhaving a relatively greater thickness. A photosensitive body has aphotoconductive layer interposed between a surface insulating layer anda conductive or insulating member. The photosensitive body is disposedaround the peripheral surface of a rotary drum, thereby providing aphotosensitive drum. The drum is rotated in one direction and firstcharging means, contemporaneous exposure-corona-discharge means,whole-surface-illuminating means, developing means, third chargingmeans, image transfer means, and cleaning means are disposed, in theorder named, peripherally of the photosensitive drum. (These means willbe referred to as peripheral means as a whole hereinafter.) The drum isuniformly charged with positive or negative charge by the first chargingmeans, exposed to the light image of an original to be reproducedcontemporaneously with application to the drum of a DC charge ofpolarity opposite to that of the first charging or with AC charge (to bereferred to as second charging), and uniformly illuminated by thewhole-surface illuminating means. An electrostatic latent image soformed is developed into a positive or negative image with toner. Ifrequired, a third charging is made before the image is transferred to acopy paper. In this case, the copy paper is electrostatically attractedby the photosensitive drum so that it is separated by a novel andusefulseparating means in accordance with the present invention. The imagetransferred to the copy paper is fixed to the copy paper.

The present invention will become more apparent from the followingdescription of the preferred embodiment thereof taken in conjunctionwith the accompanying drawings in which:

FIG. 1 is a perspective view of one preferred embodiment of the presentinvention;

FIG. 2 is a longitudinal sectional view thereof;

FIG. 3 is a sectional view, on enlarged scale, of a photosensitive drumand an original carrier therefor,

FIG. 4 is a longitudinal sectional view 'of the original carrier;

FIG. 5 is a front view illustrating the gear train for driving thephotosensitive drum;

FIG. 6 is a perspective view of the original carrier and itsreciprocating drive mechanism;

FIG. 7 is a detailed view of an exposure means;

FIG. 8 is a transverse sectional view of developing means;

FIGS. 9(1) and 9(2) and FIG. 10 are detailed views of a developing agentsupply-device;

FIGS. 11(1) and 11(2) are detailed views of copy paper feeding means;

FIGS. 12(1) and 12(2) are perspective views illustrating image transfermeans and copy paper separating means;

FIG. 13 is a longitudinal sectional view including an illustration offixing means in accordance with the present invention;

FIG. 14 is a side view of a mechanism for moving toward and away fromthe photosensitive drum, an image transfer roller, the cleaning means,the developing means and other means in unison with each other; and

FIG. 15 is a perspective view thereof.

FIG. 1 is a perspective view of an electrophotographic apparatus inaccordance with the present invention. An original carrier 11 is mountedupon the top of the housing and an original is placed upon the originalcarrier 11 with its pattern to be reproduced facing downwardly. Theoriginal carrier 11 is reciprocated. The copies reproduced aredischarged from an outlet to a tray 12. Copy paper sheets P are fed oneby one from a feeding station 55.

FIG. 2 is a longitudinal sectional view of the apparatus. A rotary drum2 has a photosensitive member 3 comprising a photoconductive layerinterposed between an outermost insulating (insulative) layer and aconductive or insulating layer whereby a photosensitive drum 1 isconstructed. The photosensitive drum 1 rotates in the directionindicated by the arrow and a first charging means 4, contemporaneousexposurecorona-discharge means 5, means 6 for exposing the whole surfaceof the photosensitive drum 1,developing means 7, third charging means 8,means 9 for transferring an image from-the photosensitive drum to a copypaper and cleaning means 10 are disposed around the periphery of thephotosensitive drum 1 in the order named.

The photosensitive member 3 upon the drum 1 is charged with positive ornegative charge by DC corona discharge by the first charging means 4. Bythe contemporaneous exposure-corona-discharge means 5, thephotosensitive member 3 receives DC corona discharge of polarityopposite to that of the first charge or AC corona discharge (which willbe referred to as second charging contemporaneously with projection of alight or radiation image of the pattern of an original to be reproducedupon the photosensitive drum 1, thereby forming an electrostatic latentimage.

Next, the electrostatic latent image thus formed upon the photosensitivemember 3 is' uniformly irradiated by the whole-surface illuminationmeans 6, such as a fluorescent lamp, so that the field of theelectrostatic latent image external to the drum is intensified, therebyforming upon the surface of the photosensitive drum 1 an electrostaticlatent image having high contrast. The latent image thus obtained isdeveloped into a visible image by developing means 7 with toner chargedoppositely to the polarity of the electrostatic latent image or with thetoner having the same polarity as that of the latent image. Preferably,the magnetic brush method or the fur brush method is used. The thirdcharging means 8 is not necessarily required, but it may beadvantageously used with a suitable polarity in order to improveefficiency in transferring the powder image upon the photosensitivemember 3 to an image recording medium (which is generally a paper sheetand will be referred to as copy paper hereinafter). The powder image istransferred electrostatically to the copy paper P by the image transfermeans 9. The toner still remaining upon'the photosensitive drum 1 isremoved by the cleaning means 10, such as a roller.

The copy paper P bearing thereupon the powder image transferred from thephotosensitive drum is separated from the drum 1 and the transferredimage is fixed by the fixing means. The copy paper bearing the fixedimage is discharged through an outlet.

The apparatus in accordance with the present invention includes theabove described electrophotographic processing station, the originalcarrier, drive means for driving the original carrier, exposure means,copy paper feeding means, image transfer and copy paper separationmeans, fixing means, an operational control system, etc. the arrangementof which characterizes the present invention. The above described meansand system will be described in more detail hereinafter.

ORIGINAL CARRIER AND DRIVE MECHANISM As shown in FIG. 3, the originalcarrier 11 runs horizontally upon an angle rail 13 and a round rail 14laid between the frames of the main body through a roller 17 and ahand-drum-shaped roller 18 which are rotatably fixed to the channels 16and 16 (See FIG. 6)

which in turn are securely fixed to the side edges of the under-surfaceof the inner frame 15 of the original carrier 3. The lateral vibrationsof the original carrier 3 are received by the roller 18 and the rail 14while the vertical vibrations are damped or absorbed by springs 20through the roller 19 which is vertically movably supported in thechannel 16 and is placed in contact with the lower side of the rail 14.

As shown in FIG. 4, a transparent original supporting glass 21 is placedupon the inner frame 15 of the original carrier 3 and an original holder22 is provided for closely pressing the original M against the originalsupporting glass 21. The original holder 22 comprises an arm 51pivotably fixed at 50 to the inner frame 15 for rotation in a planeperpendicular to the original carrier, a retaining member 54 U-shaped incross section and pivotably fixed by a pin 52 to the arm 51 and a rubbersheet 53 fixedly retained by the retaining member 54. The originalholder 22 may be raised depending upon the thickness of the original Mas shown by broken lines in FIG. 4 so that even a thick original M maybe pressed against the glass 21 in a satisfactory manner withoutnecessity to substantially increase the length of the rubber sheet 52.

A rotary shaft 26 of the photosensitive drum 1 is joumaled by bearings23 which are securely fixed to the side plates 1 and 1 of the drum 1 andby a drum supporting member 25 which in turn is securely fixed to thebottom plate 24 of the housing. A drum drive gear G4 is carried by thedrum shaft 26 through the bearing 23. The drum side plate 1 is providedwith an outwardly extending projection 27 which is fitted into a recess28 formed in the boss of the gear G4, so that the drum 1 may be mountedupon and detached from the shaft 26 by sliding the former relative tothe latter. The drive gear G4 has a control cam 33 (see FIG. 5) formedintegrally therewith so as to control switches MS-4 to MS-8, whichconstitute a control unit. The end remote from the drive gear G4 of thedrum shaft 26 is journaled in an auxiliary side plate 29 which isdetachably fixed to the bottom plate 24 so that the drum 1 may bereadily mounted and detached.

The drum 1 is rotated in one direction by a main motor MT fixed to thedrum supporting member 25, through a gear G1, idlers G2 and G3 and thedrive gear G4 carried by the drum shaft 26. In exposure, the originalcarrier 11 is displaced in the direction indicated by the arrow a inFIG. 2 and upon completion of the exposure, the carrier 11 is reversedin the direction indicated by the arrow b and returned to its initial ornormal position. As shown in FIG. 6, two belts or wires and 31, eachhaving an end secured to the channel 16 fixed to the undersurface of theoriginal carrier 11, are wrapped in opposite directions around the guidepulleys 30 and 31 and around an original carrier drive pulley 30pcarried by the drum shaft 26, and then the other ends of the belts orwires 30 and 31 are securely fixed to the pulley 30p. The drive pulley30p is rotated in forward and reverse directions in one cycle of thecopying operation, through two clutches C- 1 and C-2 as shown in FIG. 5.In one undirectional or forward stroke of the original carrier 11, theclutch C-2 is actuated so that the driving force from the motor MT istransmitted to the drive pulley 30p integral with the gear G7 throughthe gears G1, G2, G3, G4 and G5, the clutch C-1 and the gears G6 and G7,so that the drive pulley 30p is rotated in the direction indicated bythe arrow in FIG. 6. Therefore, the wire 30 is wound around the drivepulley 30p so that the original carrier 11 is driven in the directionindicated by the arrow a at a predetermined velocity, whereby theoriginal M (See FIG. 4) is exposed through a slit. That is, the lightimage ofthe original is projected upon the drum 1 through 'thecontemporaneous exposure-corona discharge means 5 sothat anelectrostatic latent image is formed upon the photosensitive drum 1which is previously charged by the first charging means 4.

It is to be noted that in the case of the reproduction of copy at amagnification of unity, the peripheral velocity of the drum 1 is equalto the velocity of the original carrier 11 in the forward stroke. Whenthe original carrier 11 reaches the end of the forward stroke, a strokecam 32 (See FIGS. 3 and 6) fixed to the channel 16, of the originalcarrier 11 actuates a microswitch MS-l which is securely-fixed to theleft end of the frame of the main body so that the clutch O2 isactivated while the clutch G1 is deactivated. Thus, the drum 1 continuesto rotate in the same direction while the drive pulley 30p is reversedin rotation so that the original carrier 11 is returned to the initialposition in the direction b. It is seen that the original carrier 11 maybe quickly returned to the initial position by suitably determining theratio of the number of teeth of the gear G6 for the forward stroke tothat of the gear G8 for the return stroke, both of which gears areselectively engaged with the gear G7. Thus, the copying operation can bemade at a high speed.

Upon returning of the original carrier 11 to the initial position (atthe right end), the stroke cam 32 actuates a rnicroswitch MS-2 (See FIG.6) fixed to the right end position of the main body so that the mainmotor MT is temporarily retarded whereby the original carrier is braked.After a suitable time delay, the rnicroswitch MS-3 is deactivated, sothat the clutch C-2 for the return stroke is de-energized, therebyprecisely retuming the original carrier 11 to the initial position anddisconnecting the carrier from its drive mechanism.

On the other hand, the drum 1 is temporarily braked and stopped but thebrake is released after a very short time (a few to tens ofmicroseconds), so that even when the original carrier 11 is stopped, thedrum 1 continues its rotation and is finally stopped when the homeposition cam 33 carried by the drum drive gear G4 deactivates thernicroswitch MS-4. The above two-step operation is for absorbing theinertia of the original carrier in the retum stroke. For this purpose,the stroke of the original carrier 11 is made relatively shorter thanthe whole stroke of the drum.

EXPOSURE MEANS The illumination system 34 includes a light source forilluminating the original such as a fluorescent lamp 35 with areflector, a light shielding plate 36 and a cooling fan (not shown) forcooling the lamp 35 so as to prevent reduction in the intensity of lightemanating therefrom.

. The cooling air is directed in the longitudinal direction of a chamberdefined by the shielding plate 36, the original carrier 11 and anoptical unit (black box) 37 so thatthe lamps 35 are effectively cooledover the whole length thereof. .The current in excess of a rated currentis maintained in lamp 35 during exposure, thereby increasing theintensity of illuminating light, but during non exposure rated currentflows through the lamp so that it is always illuminated. Thus, there isno waiting time in printing operations and the service life of the lamp35 may be increased.

The light from the lamps 35 illuminates the original supported upon theoriginal carrier 11 and light reflected from the original is transmittedthrough a transparent, dust proof glass 39 which is held in posi tionupon the black box 37 by retaining members 38. The reflected light isdirected away from the drum as shown by a'first mirror 40 which isinclined at about 45 relative to the horizontal, to an in-mirror typelens 41. The in-mirror type lens 41 is a conventional lens divided intotwo sections along the axis of symmetry and a mirror is positioned atthe center. The light reflected by a second mirror 41, passes throughthe lens 41 again and is projected upon the drum 1 through thecontemporaneous exposure-corona discharge means 5 which is fixed to theblack box 37 in opposed relation with the drum 1 and has an exposureslit in the longitudinal direction.

The first reflecting mirror 40 is supported upon three embossedprojections of a mirror stand 44 and maintained in position by a mirrorpressure spring 43 which in turn is securely fixed to the mirror stand44. The mirror stand 44 is fixed to a stand (not shown) which is onlymovable in the horizontal direction. A pin 45 is fixed to the mirrorstand 44 at the extension of the optical axis so that the mirror stand44 may rotate about the pin 45. A stopper pin 46 is extended from thecenter of a stand which in turn is fixed to the carrier (not shown).This pin 46 is externally threaded at 48 so that the pin 46 may bemovable. The mirror stand 44 is so biased by a spring 47 that the mirrorstand 44 is normally in contact with the pin 46 so that the angle of themirror relative to the horizontal axis may be adjusted by moving the pin46. The adjustment of the parallelism relative to the drum 1 and theoptical length is made by displacing the carrier in the horizontaldirection. A transparent dust proof member 49 is fixed to the opticalunit (black box) 37 so as to completely seal the optical unit 37. When aconductive member such as NESA glass is used as the dust proof member,the charging efficiency of the contemporaneous exposure-corona-dischargemeans 5 may be improved.

ELECTROPHOTOGRAPHIC PROCESSING STATION 'Ihe photosensitive drum 1 isstarted in response to the depression of a start switch. As describedhereinabove, the light image of the original is projected upon the drum1 simultaneously with charging of the drum 1 by the contemporaneousexposure-corona discharge means 5. Next the drum 1 is uniformlyilluminated by light emanating from the lamp 6, whereby an electrostaticlatent image having a high contrast may be formed upon the drum 1.

The developing means is of a box-shaped construction as shown in FIG. 8having side walls 101 and a bottom plate 100, and includes two magneticbrushes 102 and 103 rotatably journaled between the opposing side walls101, two blades 104 and 105, and guide rails 108 and 109 upon whichrests a hopper 111. Each of the magnetic brushes 102 and 103 is amagnetic roller having a plurality of alternately arranged differentpoles carried by a non-magnetic shaft. It is to be noted that differentpoles of the magnetic brushes 102 and 103 are opposed to each other.

A developing agent 1 consists of colored, finely divided powder (toner)and finely divided iron powder (carrier). The toner and the carrier aremixed uniformly by a pair of mixing rollers 106 and 107 and then movedtoward the first magnetic roller 102 to raising the mixture by theblades. Then the developing agent is attracted by the first roll 102 andis transferred to the second roller 103 so that the so-called magneticbrush uniform attraction of developing agent occurs. When the leadingportion of the magnetic brush having less magnetic flux contacts thesurface of the drum 1 bearing an electrostatic latent image, the leadingportion of the magnetic brush is attracted electrostatically by the drum1 and is finally cut off, so that fog and other undesired stains areformed upon the image. Therefore, in order to eliminate this defect, theblades 104 and 105 are provided for the magnetic brushes so that thebrush in excess of a predetermined height may be cut off. The magneticbrushes are rotated in the directions shown in FIG. 8 and the hard orbristle magnetic brush in the space defined intermediate the brushes andthe drum 1 is placed in sliding contact with the surface of the drum 1,thereby developing the latent image into a visible image.

The mixing roll 107 serves to uniformly mix the condensed developingagent 112 dropped from the hopper 111 immediately above the mixing roll107, with the developing agent in the developing means and to supply thedeveloping agent toward the mixing roll 106. The hopper 111 is movedinto and away from the developing means along the rails and guide rails108, 109 and 120 disposed between the side walls 101 of the developingmeans. The hopper 111 has a U-shaped main body 113 and guide blocks 114(See FIG. 10) at both ends of the main body 113. The bottom 116 has aplurality of openings 115 extending laterally and spaced apart from eachother in the longitudinal direction by a suitable distance. A movingplate 117 having a plurality of openings 118 having the same dimensionsand pitch as those of the openings 115 is interposed between the guideblocks upon the bottom 116 for slidable movement in the longitudinaldirection. (See FIG. 10). Normally the moving plate 117 is so biased bya spring that the openings 118 of the moving plate 117 will not registerwith the openings of the bottom 116. Therefore, only when the developingagent feed button 119 is depressed do the openings 115 register with theopenings 1 18 so that the developing agent 112 is dropped into thedeveloping means. Hopper guide rails 120 are fixed to the lower sidewalls of the main body 113 in such a manner that each lower free end 121of the guide rail 120 is bent inwardly (See FIG. 8). A control plate 122for controlling the quantity of developing agent to be dropped hasopenings or slits having the same dimensions and pitch as those of theopenings 116 and 118 and is interposed between the guide plates 120 andthe bottom 1 16 for slidable movement in the longitudinal direction inorder to control the quantity of the developing agent to be droppedthrough the openings 1 15 of the bottom 116. That is, the maximumquantity of developing agent is dropped when the openings of the bottom116, the moving plate 117 and the control plate 122 coincide with eachother. The quantity of the developing agent to be dropped is controlledby the control plate 122.

FIGS. 9(1) and 9(2) illustrate a mechanism for automatically depressingthe hopper button 119 of the condensed developing agent feeding hopper.A cam gear G22 is driven by a gear G20 carried by a shaft 123 of thesecond roller 107 through a clutch gear G21. The cam gear G22 makes onerotation in response to each feeding of a copy paper. The projection 125of a cam 124 made integral with the gear G22 engages a counter lever 126so that a counter ratchet wheel 127 rotated by one tooth. That is, thecounter ratchet wheel 127 advances by one tooth when each copy paper isfed. A projection 128 extends from one side face of the counter ratchetwheel 127 and engages the clutch releasing lever 129 to push the clutchreleasing lever 129 and disengage the lever from a stepped portion 132of a clutch sleeve 130. Therefore, a spring 130 loaded in the sleeve 130winds itself around the bosses of the clutch gear G21 and that of thehopper cam 130 so that the gear G21 drives the cam 130 whereby thehopper button 119 is depressed by the cam surface 130 Thus, the openings118 of the moving plate 117 coincide with those of the bottom 116thereby supplying the developing agent. The clutch releasing lever 129actuated by the counter ratchet wheel 127 may be immediately returned toits initial position so that when the clutch sleeve 130 makes onerotation, the leading end 131 of the clutch releasing lever 129 engageswith the stepped portion 132 of the sleeve 130, thereby stopping thesleeve 130. Then, the spring clutch is released and the hopper cam isstopped. Unless the counter ratchet wheel 127 is advanced by one toothas one copy paper is fed so that the projection or pin 128 actuates theclutch releasing lever 129, no developing agent is supplied. Thedeveloping means 7 is activated by a signal generated when the copypaper P passes over the microswitch MS-9 between the feed rollers 58 and59 (See FIG. 2) as will be described in more detail hereinafter so thatunless copy paper is feed, reproduction is not commenced even when themachine is driven, and no excessive developing agent 112 is supplied.

COPY PAPER FEEDING STATION As shown in FIG. 2, the feeding stationcomprises copy paper feeding means 55 and copy paper transporting means56. The copy papers in the feeding means 55 are fed toward thetransporting means 56 one by one by a feed roller 57 which rotates inresponse to a signal from the control means 33 (See FIG. Thetransporting means comprises a first, second and third pairs of rollers58, 69 and 60. The first roller 58 is intermittently driven in responseto the signal from the control means 33 in order to adjust the time whenthe image upon the drum 1 is transferred to the copy paper P in thetransfer means 9 and to ensure the registration of the leading edge ofthe copy paper P with that of the original M. The second and third feedrollers 59 and 60 are normally driven so as to transport the copy paperP to the transfer means 9. Since the first roller 58 is not driven whena copy paper P is fed from the feeding means 55 by the feed roller 57,the copy paper P is bowed as indicated by the broken line so that theleading edge of the copy paper P is disposed parallel to the axis of thefirst roller 58. In response to the signal from the control means 33,the first roller 58 is driven so that the copy paper P is transported bythe second and third rollers 59 and 60 into the image transfer means 9in such a manner that the leading edge of the copy paper P is registeredwith that of the powder image upon the photosensitive drum 1.Thereafter, the powder image upon the drum 1 is transferred to the copypaper P when the latter is pressed against the drum 1 by a pressure ortransfer roller 9.

The switch MS-9 is interposed between the first and second rollers 58and 59 in the path of the copy paper so as to detect the passagethereof, thereby controlling the developing means 7. When no copy paperis transported so that the switch MS-9 is not actuated, the developingmeans 7 is not activated. Therefore, the electrostatic latent imageformed upon the drum 1 will not be developed so that the transfer roller9 which is normally made in rolling contact with the drum 1 is notstained. No load is applied to the cleaning roller 61 in the cleaningmeans 10. The copy paper feeding means 55 will be described in moredetail with reference to FIGS. 11(1) and 11(2). A copy paper stand 199is detachably mounted through guide rails or the like upon the main bodyof the photocopying machine. A pair of L-shaped guides 200 and 201 areplaced upon the stand 199. The right guide 200 is securely fixed to thestand 199 while the left guide 201 may be displaced on a slide pin 202extending from the undersurface of the left guide 201 and being movablein a guide slot 203 formed in the stand 199 depending upon the sizes ofthe copy papers. The rear portions of both of the guide plates 200 and201 are cut away so as to form notches into which are fitted copy paperpressure members 205 biased inwardly by springs 204. Thus, the copypapers P are held in position with their side edges being held by thepair of right and left guides 200 and 201 to eliminate undesiredresistance, and the separation of the copy papers P is much facilitated.

Separating levers 207 and 208 are vertically pivotably fixed to theouter side edges of the guides 200 and 201 by pins 206. At the leadingor free end of each of the separating levers 207 and 208 is formed aseparating pawl consisting of a vertically downwardly bent portion 209for preventing the displacement of the copy papers P and a horizontalportion 210 for holding the comer of the paper from above. The copypaper P advanced by the feed roller 57 is stopped by the verticalportion 209 of the separating pawl, but the center portion of the copypaper P is still advanced so that the leading edge stopped by theseparating pawl is buckled, whereby only the uppermost copy paper isdisengaged from the pawl and advanced.

A stopper 240 is fixed to the leading end of the stand 199 by a pin 241in such a manner that the stopper 240 may be normally held in raisedposition by a spring (not shown). Thus, the stopper 240 may be used as areference in placing the copy papers upon the stand 199 because thepawls are not used since the separating levers 207 and 208 then lifted.A pawl releasing lever 213 for raising the separating lever 208 is fixedto the stand 199 outwardly of the movable guide 201 in such a mannerthat the lower end is extended through the opening formed through thestand 199 and pivotably fixed to the stand 199 by a pin 211. A cam 215is also carried by the pin 211 in such a manner that when the lever 213is raised as shown in FIG. 11(1) the cam 215 pushes the rear lowersurface of the lever 208 so as to raise-it, thereby permitting theplacing of copy papers upon the stand 199.

Another cam 216 is also carried by the pin 211 so that when the lever213 is raised, pressure acts upon the plate spring 212 bridging themovable guide pins 202. That is, the pressure placed upon the stand 199from the movable guide 201 is released so that the latter may bedisplaced. A shaft 222 extends over the stand 199 between bearing plates223 and 224 securely fixed to the main body of the photocopying machineoutwardly of the stand 199. A tubular shaft 225 is fitted over one half(the lower half in FIG. 11(2)) of the shaft 222 and bearings 226 and 226are interposed between the shaft 222 and the tubular shaft 225. A shaft244 is joumaled in the leading ends of an arm 242 loosely fixed to theshaft 222 and another arm 243 securely fixed to the tubular shaft 225.The copy paper feed rollers 57 are carried by this shaft 222. The shafts222 and 244 are drivingly coupled to each other by a chain 245.

A drive clutch gear G31 carried at one end of the shaft 222 is meshedwith a normally rotating gear G30 through a clutch C-5 in response to acopy paper feed signal so that the rollers 57 are rotated through theshaft 222, the sprocket wheels 246 and 247, the chain 245 and the shaft244. The gear G31 is driven by the chain 220 wrapped around a sprocketwheel 221.

As shown in FIG. 11(2), a boss 227 is securely fixed to the bearingplate 224 coaxially with the shaft 225. A knob 299 is fitted into theboss 227 and a spring 230 is loaded between the knob 229 and the tubularshaft 225. The knob 229 is pulled out of the boss 227 against the spring230 and rotated through an angle and held in position by the engagementof a suitable projection and recess, thereby pressing the feed rollers57 against the copy papers through the tubular shaft 225, the arm 243and the shaft 244 by the spring 230. The pressure acting upon the copypapers may be adjusted by the knob 229, thereby ensuring the smoothfeeding of copy papers irrespective of the difference in quality.

As the copy papers upon the stand 199 are used, the positions of thefeed rollers 57 are gradually lowered so that the tubular shaft 225 iscaused to rotate in the counterclockwise direction. This rotation isdetected by a cam 248 carried by the tubular shaft 225 and a microswitchMS-30 securely fixed to the bearing plate 224. That is, the number ofcopy papers upon the stand 199 may be detected so that when the numberof copy papers becomes less than a predetermined number, an alarm devicesuch as a lamp in the control panel is turned on.

IMAGE TRANSFER AND PAPER SEPARATING MEANS The copy paper fed from thefeeding means 55 and transported toward the image transfer means by therollers 58, 59 and 60 is pressed against the powder image upon the drum1 by the transfer roller 9. Preferably the transfer roller 9 is made ofan electrically conductive material. Separating means generallydesignated by 300 is disposed in the image transfer means so that thecopy paper may be separated from the drum 1 after the powder image hasbeen transferred. That is, as shown in FIGS. 2 and 12, a copy paperseparating band 301 is extended forwardly and rearwardly of the powderimage transfer position, that is, the line of contact between thetransfer roller 9 and the drum 1, around the transfer roller 9. Forexample, the separating band 301 is a polyester resin film 50 p. inthickness and contacts one side or marginal edge of the copy paper Pover at least 10 mm.

The copy paper P is admitted into the nip between the drum 1 and thetransfer roller 9 from a guide 250 and one side edge of the copy paperis disposed between the transfer roller 9 and the separating band 301.After passing through the transfer position, the copy paper is guided bythe undersurface of the separating band 301 along the transfer roller 9so that the copy paper may be readily separated from the drum 1 and thenfed into the fixing means. The peripheral portion 9, of the transferroller 9, around which is wrapped the separating band 301 (See FIG.12(1)) is made of a metal having a smooth surface and has a diameterslightly smaller than that of the transfer roller 9, which is made of anelastic material such as conductive rubber, so that the separating band301 is not placed in contact with the drum 1, thereby preventing wear ofthe band 301. When the transfer roller 9 has a stepped metallic rollermember 9,, the application of a potential to a conductive transferroller or grounding thereof may be facilitated. The separating band 301has its both ends securely fixed by retainers 303 and 304, but when theseparating belt 301 is so positioned around the transfer roller 9 thatthe belt 301 is not made in contact with the photosensitive drum 1 asdescribed hereinabove, an endless belt may be used. The band 301 isgiven a suitable tension by a tension pin 306 having a spring 307.

FIXING MEANS The fixing means (FIGS. 2 and 13) comprises infrared lampsor heaters 400, a blower 401 and a conveyor belt 402 which is advancedin the direction indicated by the arrows. The blower 401 blows heatedair upon the copy paper P to which is transferred the powder image fromthe drum 1 so that the powder image is fixed to the copy paper P. Theheated air from the blower 401 also ensures positive holding of the copypaper upon the conveyor belt 402 spaced from the heaters 400. The copypaper bearing the fixed image is discharged out of the fixing meansoutlet 16 through a pair of discharge rollers 403 and 404.

Now referring more particularly to FIG. 13 which illustrates oneembodiment of the fixing means in accordancewith the present invention,the conveyor belt 402 is wrapped around the drive roller 482 and a guideroller 483 between the transfer roller 9 and the pair of dischargerollers 403 and 404 and the radiation heating means 471 is disposedabove the conveyor belt 402.

Preferably, the conveyor belt unit may be detachably mounted upon thephotocopying machine so that the inspection, repairs, etc. may befacilitated. For this purpose, an opening 473, into which may be fitteda side wall 472, is formed through the side wall 600 of the main body ofthe machine. The conveyor belt unit may be guided by guide rails 474.The conveyor belt 402 may be made of an electrically insulating materialhaving a resistance to heat, such as tetrafluoroethylene containingglass fibers. A charging electrode 475 and a grounding electrode 476 aredisposed in the path of the conveyor belt 402 so that charge may beimparted thereto. The charge imparted to the conveyor belt 402 is thesame polarity as that of the charge imparted from the third chargingmeans 8. An insulating block 477 for enclosing therein the electrode 475is so disposed as to move in and out by a guide '477 the bottom platebetween the side walls 472 having heat resisting materia] coated orlined upon the inner surface thereof.

The radiation heater means 471 is supported between the side walls 600by insulating material. In the instant embodiment, a pair of reflectors478 have mirror surfaces directed toward the conveyor belt 402 and theheating elements 400 are disposed in the reflectors 478 respectively. Aduct 479 is formed behind the reflectors 478 and incorporates thereinthe blower 401 so that the air in a space defined between the reflectors478 is sucked through an opening 480 and blown against the copy paper Pthrough an opening 481 at the position where thevcopy paper P is loadedupon the conveyor belt 402. A heat insulating chamber 484 is provided inorder to prevent the transmission of heat from the heating means 471 tothe main body of the photocopying machine.

Since the conveyor belt 402 is imparted with the charge of the polarityopposite to that given by the third charging means 8, by the electrodes475 and 476, the copy paper P loaded upon the conveyor belt 402 iselectrostatically attracted thereby during the transportation. That is,when the polarity of the charge of the powder image is negative whilethe polarity of the charge imparted from the third charging means 8 isalso negative, positive charge is imparted to the copy paper P from theconductive transfer roller 9 which is grounded. Thus, the negative orpositive charge, for example, from 3 to 6 KV is imparted to the conveyorbelt 402 by the electrodes 47 5 and 476, thereby attracting the copypaper to the belt 402. Since the heat insulating belt 402 is elevated toa temperature of about 200C because it is always heated by the heatingmeans 471, the toner is fused and fixed upon the copy paper P.

The copy paper P upon the conveyor belt 402 is heated not only by theheaters in the reflectors in the radiation heating means 471, but alsoby the heated air about 150 to 200C from the blower 401. As describedhereinabove, the heated air around the heaters is sucked by the blower401 through the opening 480. That is, the heated air flows upon the copypaper upon the belt 402 and heats the copy paper. Thereafter, the heatedair passes through the duct 479 and is then blown through the opening481 upon the copy paper upon the belt 402. Therefore, the copy paper aswell as the powder image thereupon are preheated, thereby preventingcurling of the copy paper due to the sudden heating. The heated air fromthe blower 401 serves to hold the copy paper upon the conveyor belt 402which is also attracted electrostatically thereby. Since the heated airis circulated, temperature variation may be prevented so that the belt402, heating means 471 and other parts may be maintained at a uniformtemperature and the thermal efficiency may be improved. According to thepresent invention, the toner may be fixed to the copy paper in a veryeffective manner by the direct heating of the copy paper as describedhereinabove. The toner is prevented from directly contact the heatingelements so that complex means for preventing the offset described aboveis not required. Furthermore, even though the copy paper is transportedupon the belt, no curling is produced, whereby jamming of copy paper maybe prevented.

CLEANING MEANS The toner remaining upon the drum 1 even after the powderimage is transferred to the copy paper may be removed by the cleaningmeans comprising a cleaning roller 61. The cleaning roller 61 comprisesa rotary shaft 500, a roller 501 made of an elastic material and a cloth502 wrapped around the roller 501. The cleaning roller 61 is rotated incontact with the drum 1 in a direction of rotation opposite to that ofthe drum 1. The toner attached to the cleaning roller 61 is removed by abrush roller 505 having hard brushes 503 extending from a rotary shaft504. The removed tonner is dropped into a toner receiving box 506. Apartition wall 507 in the box 506 is for preventing the dispersion ofthe toner from the box 506 to the drum 1. Because of the auxiliarycleaner 508 (See FIG. 2) comprising an elastic body covered with acloth, even a very small quantity of the toner still remaining upon thedrum 1 after it is cleaned by the cleaning roller 61 may be completelyremoved from the drum. The auxiliary cleaning means 508 is detachablymounted so as to be replaced at a suitable time interval.

OTHER MEANS AND MECHANISMS Since the drum 1 is cleaned by the cleaningmeans each time one copy is reproduced in the manner describedhereinabove, it is necessary to prevent relative deviation andseparation of the photosensitive member 3 from the supporting drum 2 dueto the pressure applied to the drum 1 by the cleaning roller 61. Thatis, the photosensitive member 3 must be securely held upon thesupporting drum 2. In order to clean all over the peripheral surface ofthe photosensitive drum 1, the width of the cleaning roller 61 (in theaxial direction) must be longer than that of the drum 1, so

that the stronger pressure tends to act upon the side edges of the drum,thereby causing the damage thereto. In order to prevent this,photosensitive member retaining elements 13 (see FIG. 3) having an outerdiameter equal to that of the drum 1 are attached to the latter so as toprotect the photosensitive member 3, to improve the durability of thedrum 1 and to reduce the cost. To remove or detach the drum 1, theauxiliary bearing plate 29 is detached from the bottom plate 24 and thenthe drum 1 is displaced toward the left in FIG. 3, thereby pulling itout of the shaft 26.

This is necessary for inspection and repair of the various meansdisposed around the periphery of the drum 1 and for replacement thereof.Thus, it is required that the transfer roller 9, the cleaning roller502, the developing means 7 and so on must be moved away from thedrum 1. Extensive time is required to separately move away from the drum1 each of the above means and the relative positions of these means willbe deviated when they are returned to their normal operative positions.Thus, overall adjustment of the photocopying machine would then berequired with resultant time loss, and a complex, tedious operation.

In order to eliminate this, the present invention contemplates arrangingthese means around the periphery of the drum so as to be moved towardand away from the drum 1 in unison by a link mechanism. As shown inFIGS. 14 and 15, the transfer means 9, the fixing means and the cleaningmeans are all carried by a common supporting frame 600 while thedeveloping means is carried by a supporting member 602.

In order to move toward and away from the drum 1 these peripheral means,a lever handle 603 is provided. When the lever handle 603 is movedtoward the position indicated by the broken lines in FIGS. 14 and 15, ashaft 604 and a guide plate 611 are rotated in the counterclockwisedirection. In the guide plate 611 is formed a guide slot 612 in such amanner that the guide slot 612 may approach the shaft 604 as the guideplate 611 is rotated, in the clockwise direction. A pin 614 of anL-shaped lever 613 is fitted into the slot 612 so that the lever 613rotates about its pin 616 as the guide plate 611 is rotated. A pin 618of a link 617 is fitted into an elongated slot formed in the forwardportion of the lever 613 so that the link 617 lifts a lateral shaft 624thereby rotating levers 622 about a shaft 621 in the counterclockwisedirection. Therefore, a lateral bar 627 and the supporting frames 600securely fixed thereto at both ends thereof are moved in the directionindicated by the arrow d in FIGS. 14 and 15 since the shaft 625 isconnected to the lateral rod 627 through a ring 623, a link 626 and aring 601. Thus, the transfer roller 9, the fixing means and the cleaningmeans carried by the supporting plates 600 are moved away in unison fromthe drum 1.

When the lever 622 and the lateral rod 625 are rotated in thecounterclockwise direction, the links 605 connected to the lateral rod625 are rotated about the shaft 604 in the counterclockwise directionwhile being guided along the elongated slots 607 so that the lever 629carried by the shaft 628 is rotated in the clockwise direction throughthe lateral rod 603, thereby moving the developing means supportingmember 602 in the direction indicated by the arrow 0.

It is therefore seen that all of the peripheral means around the drum 1are moved away therefrom, whereby the drum 1 may be readily detached.Upon returning to the initial position of the lever handle 603, theabove described operations are reversed so that all of the peripheralmeans may be precisely returned to their normal positions relative tothe drum 1.

From the foregoing, it is seen that the electrophotographic copyingmachine in accordance with the present invention is compact in sizebecause the first charging means, the contemporaneous exposuresecondcharging means, the whole surface illumination means, the developingmeans, the third charging means if required, the image transfer meansand the cleaning means, all of which are required forelectrophotographic processing, are disposed around the drum; theoriginal carrier is disposed above the drum for reciprocal movement; theoptical exposure means and the cleaning means are disposed laterally ofthe original carrier; and the copy paper feeding means, the transfermeans and the fixing means are disposed downwardly of the drum.

The optical system is disposed upwardly of the developing means butlaterally of the drum and is sealed by an optical unit so that the lens,mirrors, etc. of the optical system may be completely prevented frombeing contaminated or stained by the toner, dust and so on. The copypaper separating band is interposed between the transfer roller and thedrum so as to guide the copy paper awaY from the drum along theseparating band, thereby smoothly and positively separating the copypaper from the drum.

The drum is rotatably carried by the main shaft and is drivingly coupledto the drive means through the coupling means disposed at one end of thedrum. The cleaning means and the transfer means are supported by thecommon supporting members so that these means may be moved toward andaway from the drum by operating the lever handle, whereby the mountingand detachment of the drum is much facilitated and peripheral meansaround the drum may be inspected, repaired, and lubricated in a verysimple yet positive manner.

What is claimed is:

1. An electrophotographic copier comprising a housing, a shaft supportedin said housing, a carrier adapted to receive an original to bereproduced, a photosensitive drum supported for rotation on said shaft,means for projecting a light image of said original onto the surface ofsaid drum, means for developing electrostatic images formed on said drumsurface, means for feeding copy material to said drum, means fortransferring said developed electrostatic images to said copy material,means for mixing said transferred images on said copy material and meansfor cleaning said drum surface, support apparatus for supporting each ofsaid means peripherally of said drum surface, said support apparatusincluding a unitary support member supporting each of said developingmeans, said transfer means, said fixing means and said cleaning meansand operator-controllable to position each said supported means inoperative position relative to said drum surface or in inoperativeposition remote from said drum surface.

2. The copier claimed in claim 1 wherein said carrier comprises a framesupported by said housing for said reciprocating movement, a transparentmember in said frame for supporting said original, support armspivotally supported by said frame and a pressure plate member pivotallysupported by said arms for movement into overlying relation with saidtransparent member.

3. The copier claimed in claim 1 wherein said projecting means comprisesa lamp supported in said housing for illuminating said original andthereby providing said original light image, a first mirror fordirecting said light image away from said drum surface, means forredirecting said light image onto said drum surface and slit exposuremeans disposed intermediate said image redirecting means and said drumsurface, said image redirecting means including a second mirror and alens having two symmetrical sections.

4. The copier claimed in claim 1 wherein said feeding means includessignal generator means rendered operative on each feeding of copymaterial to said drum, said developing means being operativelyresponsive to said signal generator means.

5. The copier claimed in claim 4 wherein said developing means includesa container for developer toner and carrier, a condensed toner supplierand means responsive to said signal generator means for rendering saidsupplier operative to supply condensed toner to said container.

6. The copier claimed in claim 1 wherein said photosensitive drumcomprises a cylindrical base, a photoconductive layer overlying saidbase, an insulative layer overlying said photoconductive layer and firstand second retaining members respectively secured to opposed ends ofsaid base, said retaining members each having a diameter substantiallyequal to that of said drum.

7. The copier claimed in claim 1 further including means for separatingcopy material from said drum, said unitary support member supportingeach of said developing means, said transfer means, said separatingmeans, said fixing means and said cleaning means andoperator-controllable to position each said supported means in operativeposition relative to said drum surface or in inoperative position remotefrom said drum surface.

8. The copier claimed in claim 1 wherein said transfer means includes aroller disposed in pressure contact with said drum surface, a stripmember intervening opposed marginal portions of said roller and drum,said copy material feeding means incorporating means for positioning amarginal part of each fed copy material intermediate said strip memberand said marginal roller portion and for positioning the remaining partof each fed copy material intermediate said roller and said drum.

9. The copier claimed in claim 1 wherein said fixing means comprises acopy material inlet, a copy material outlet, a pair of rollers supportedintermediate said inlet and said outlet, a conveyor encircling saidrollers and supported for movement thereby, electrode discharge meansfor applying charge to said conveyor, and means disposed adjacent saidconveyor for heating copy material thereby conveyed.

10. The copier claimed in claim 9 wherein said fixing means includes airducting means having an exhaust port disposed adjacent said inlet forducting air heated by said heating means against said conveyor.

11. The copier claimed in claim 9 wherein said support means includes aunitary support element for detachably securing said belt, said rollersand said heating means to said housing.

v UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Eatent No. 146 lD d September 5, 1972 'Inventor(s) YOShiO ItO et a1.

It is Certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

Title page, item [56] "Eilhorn" should read --Eichorn- Y "Eisbeing"should read '--Eisbein- 3, line 32, after "charging" insert v 4, line39, "52" should read 53'--. Column 6, line 16, "The current" should read-Current flow".

7, line 30, "roll" should read "roller", I 8, line 32, "rotated" shouldread --advances--. 8, line 61, "feed" should read "fed- I Column 10,line 17, after "208" insert ----are---.

Column 13, lines. 24-25,: "contact" should read "contacting". j Column13, line 43, "tonner should read "toner", Column 13, line 65, i delete"over"; I

Column 14, line Y 2, delete "the" (second instance) Signed and T sealedthis 1st day of May 1973.

(SEAL) Attest: EDWARD M. FLETCHER, JR. ROBERT GOTTSCHALK 4 AttestingOfficer g Commissioner of Patents FORM FO-IOSO (10-69) USCOMM-DC60376-P69 v U.S,.GOVERNMENT PRINTING OFFICE I969 0-366-334 J

1. An electrophotographic copier comprising a housing, a shaft supportedin said housing, a carrier adapted to receive an original to bereproduced, a photosensitive drum supported for rotation on said shaft,means for projecting a light image of said original onto the surface ofsaid drum, means for developing electrostatic images formed on said drumsurface, means for feeding copy material to said drum, means fortransferring said developed electrostatic images to said copy material,means for mixing said transferred images on said copy material and meansfor cleaning said drum surface, support apparatus for supporting each ofsaid means peripherally of said drum surface, said support apparatusincluding a unitary support member supporting each of said developingmeans, said transfer means, said fixing means and said cleaning meansand operator-controllable to position each said supported means inoperative position relative to said drum surface or in inoperativeposition remote from said drum surface.
 2. The copier claimed in claim 1wherein said carrier comprises a frame supported by said housing forsaid reciprocating movement, a transparent member in said frame forsupporting said oRiginal, support arms pivotally supported by said frameand a pressure plate member pivotally supported by said arms formovement into overlying relation with said transparent member.
 3. Thecopier claimed in claim 1 wherein said projecting means comprises a lampsupported in said housing for illuminating said original and therebyproviding said original light image, a first mirror for directing saidlight image away from said drum surface, means for redirecting saidlight image onto said drum surface and slit exposure means disposedintermediate said image redirecting means and said drum surface, saidimage redirecting means including a second mirror and a lens having twosymmetrical sections.
 4. The copier claimed in claim 1 wherein saidfeeding means includes signal generator means rendered operative on eachfeeding of copy material to said drum, said developing means beingoperatively responsive to said signal generator means.
 5. The copierclaimed in claim 4 wherein said developing means includes a containerfor developer toner and carrier, a condensed toner supplier and meansresponsive to said signal generator means for rendering said supplieroperative to supply condensed toner to said container.
 6. The copierclaimed in claim 1 wherein said photosensitive drum comprises acylindrical base, a photoconductive layer overlying said base, aninsulative layer overlying said photoconductive layer and first andsecond retaining members respectively secured to opposed ends of saidbase, said retaining members each having a diameter substantially equalto that of said drum.
 7. The copier claimed in claim 1 further includingmeans for separating copy material from said drum, said unitary supportmember supporting each of said developing means, said transfer means,said separating means, said fixing means and said cleaning means andoperator-controllable to position each said supported means in operativeposition relative to said drum surface or in inoperative position remotefrom said drum surface.
 8. The copier claimed in claim 1 wherein saidtransfer means includes a roller disposed in pressure contact with saiddrum surface, a strip member intervening opposed marginal portions ofsaid roller and drum, said copy material feeding means incorporatingmeans for positioning a marginal part of each fed copy materialintermediate said strip member and said marginal roller portion and forpositioning the remaining part of each fed copy material intermediatesaid roller and said drum.
 9. The copier claimed in claim 1 wherein saidfixing means comprises a copy material inlet, a copy material outlet, apair of rollers supported intermediate said inlet and said outlet, aconveyor encircling said rollers and supported for movement thereby,electrode discharge means for applying charge to said conveyor, andmeans disposed adjacent said conveyor for heating copy material therebyconveyed.
 10. The copier claimed in claim 9 wherein said fixing meansincludes air ducting means having an exhaust port disposed adjacent saidinlet for ducting air heated by said heating means against saidconveyor.
 11. The copier claimed in claim 9 wherein said support meansincludes a unitary support element for detachably securing said belt,said rollers and said heating means to said housing.